Consumers continually express interest is products that can simplify the processes they use to launder clothes, help them reduce the amount of time they spend dealing with dirty laundry, and help them achieve high levels of cleanliness and softness for their family's clothing. Cleaning and softening of laundry presently requires consumers to dose two products to either different compartments of the washing machine or to dose one product to the washing machine and one product to the dryer.
The process of laundering fabric can be broken up into three basic steps: washing, rinsing, and drying. The washing step typically employs water and detergent composition comprising anionic surfactant, along with other active agents that are compatible with anionic surfactants in the unused product form and in the wash liquor formed during the washing step. After washing, the laundry is rinsed one or more times as part of the rinsing step.
Presently, laundry softening is most often and practically accomplished during the rinsing step with a liquid softening composition that is separate from the detergent composition or during the drying step. To apply liquid softening composition to the laundry in the washing machine, the liquid softening composition is introduced to the laundry during the rinsing step. The liquid softening composition may be automatically introduced into the rinse from a compartment that keeps the liquid softening composition separate from the washing composition. The compartment may be part of the agitator, if present, or another part of the washing machine that can be opened to dispense the liquid softening composition into the drum. This is often referred to as softening through the rinse. Softening through the rinse requires the consumer to dose the detergent composition and the softening composition to different locations of the washing machine, which is inconvenient.
Laundry softening can also be accomplished during the drying step using fabric softening sheets. With either of these approaches to cleaning and softening, cleaning is performed separately from softening.
Consumers find it inconvenient to have to dispense multiple products to different locations, whether the locations are part of the washing machine or the locations are distributed between the washing machine and the dryer. What the consumer would like is to be able to dose the detergent composition and the softening composition to a single location.
Unfortunately, liquid detergent compositions tend to be incompatible with softening compositions. Liquid detergent compositions comprise anionic surfactants to help clean the clothing. Softening compositions typically comprise cationic surfactants to soften the clothing. When combined in a single package, the anionic surfactant and cationic surfactant can combine and form a solid precipitate. This results in problem with stability of the combination when packaged together in a liquid form or together in a wash liquor and a decrease in cleaning performance as compared to the detergent composition in absence of the softening composition. This incompatibility problem is among the reasons that detergent compositions and fabric softening compositions are dosed and applied separate from one another. Liquid fabric softening compositions packaged separately from detergent compositions may not be preferred by some consumers due to the inconvenience of dosing the composition to the washing machine, perceived messiness, and the texture of the product.
With these limitations in mind, there is a continuing unaddressed need for a solid form through the wash fabric softening composition that can be dispensed by the consumer together with the laundry detergent to providing softening through the wash during the washing step.